An adhesive, coating, or sealant composition is selected for a particular purpose based on the final physical properties available after composition cure. These physical properties typically include tensile strength, shear strength, weathering resistance, flexibility, and in some instances transparency. Additional factors in the selection of a particular composition include not only final physical properties, but also handling properties such as precure viscosity and the rate of physical property build during cure. In a production setting rapid physical property build facilitates product throughput as components to be joined will not need to be set aside waiting for cure property buildup.
An often important physical property buildup parameter is the amount of time required for a composition to become tack free since a non-tacky composition is amenable to exposure to subsequent operations that produce debris that would otherwise contaminate a tacky composition.
A number of one part moisture curable compositions exist that provide these characteristics within a narrow range of final physical properties. Among these conventional materials are polyurethane compositions as detailed in, for example, U.S. Pat. Nos. 3,380,967 and 3,779,794; and silane terminated acrylics such as those detailed, for example, in U.S. Pat. Nos. 6,414,077 and 7,064,162. Unfortunately, the extendable range of physical properties currently attainable with existing compositions is limited.
Thus, there exists a need for moisture curable isocyanate containing formulations that afford rapid provision of a wide range of cured formulation glass transition temperatures and substrate wetting. Additionally, there exists a need for such a formulation providing rapid final physical property buildup and tolerant of being warm-applied.